2 files changed, 24 insertions, 0 deletions

diff --git a/crates/hir_def/src/nameres/path_resolution.rs b/crates/hir_def/src/nameres/path_resolution.rs
index 82528b792..7b5fe24a7 100644
--- a/crates/hir_def/src/nameres/path_resolution.rs
+++ b/crates/hir_def/src/nameres/path_resolution.rs
@@ -13,6 +13,7 @@
 use std::iter::successors;
 
 use base_db::Edition;
+use hir_expand::name;
 use hir_expand::name::Name;
 use test_utils::mark;
 
@@ -63,6 +64,13 @@ impl ResolvePathResult {
 
 impl DefMap {
     pub(super) fn resolve_name_in_extern_prelude(&self, name: &Name) -> PerNs {
+        if name == &name!(self) {
+            mark::hit!(extern_crate_self_as);
+            return PerNs::types(
+                ModuleId { krate: self.krate, local_id: self.root }.into(),
+                Visibility::Public,
+            );
+        }
         self.extern_prelude
             .get(name)
             .map_or(PerNs::none(), |&it| PerNs::types(it, Visibility::Public))
diff --git a/crates/hir_def/src/nameres/tests/diagnostics.rs b/crates/hir_def/src/nameres/tests/diagnostics.rs
index 58d69d3c6..e8e72e5ef 100644
--- a/crates/hir_def/src/nameres/tests/diagnostics.rs
+++ b/crates/hir_def/src/nameres/tests/diagnostics.rs
@@ -62,6 +62,22 @@ fn unresolved_extern_crate() {
 }
 
 #[test]
+fn extern_crate_self_as() {
+    mark::check!(extern_crate_self_as);
+    check_diagnostics(
+        r"
+        //- /lib.rs
+          extern crate doesnotexist;
+        //^^^^^^^^^^^^^^^^^^^^^^^^^^ unresolved extern crate
+        // Should not error.
+        extern crate self as foo;
+        struct Foo;
+        use foo::Foo as Bar;
+        ",
+    );
+}
+
+#[test]
 fn dedup_unresolved_import_from_unresolved_crate() {
     check_diagnostics(
         r"